The present invention relates to an auto audio/video output circuit with multiple audio/video inputs, and more particularly to such an auto audio/video output circuit which receives inputted audio/video signals from different audio/video equipment, and selects the last inputted audio/video signal for output.
A regular audio/video output device, for example a TV, has only one set of audio/video input terminals. When connecting different audio/video equipment to a TV, a selector shall be used and connected between the TV and the audio/video equipment, so that the user can select one audio/video equipment for output to the TV. Further, a variety of audio/video equipment including DVD, VDC, video tape recorder/player, V8, video cassette recorder, etc. have been developed, and have appeared on the market. Various adapters are known, and used for connection between different audio/video equipment. These adapters are commonly made from wave band switches or wave link switches. Because these switches are passive devices, they cannot automatically set the output signal channel. When in use, the user has to find the accurate output channel for signal output. Because these switches are mechanical devices, they wear quickly with use. There are also known remote-controlled audio/video adapters for controlling the connection between audio/video equipment. These remote-controlled audio/video adapters are convenient in use, however their manufacturing cost is high.